Few people have filed their taxes and not had doubts creep to mind: Did I do this right? Did I claim everything correctly? Could the IRS come knocking?

This year, that doubt is paying off for scammers.

Officials say the year's hottest tax-season scam has so far bilked thousands of taxpayers out of more than $1 million. The IRS and the Treasury inspector general for tax administration say it's the largest ever phone fraud scam targeting taxpayers.

A Butler County woman is among the victims, Prosecutor Michael Gmoser announced Thursday. The 55-year-old woman, whose name hasn't been released, was coerced into paying $14,000 to avoid imprisonment.

Here's how the scam works: The victim gets a phone call from someone claiming to be an IRS agent and accusing the victim of owing the government money.

The supposed agent has details that seem to confirm his legitimacy, such as portions of the victims' Social Security numbers or details about their jobs and homes. The agent warns that an investigation is underway and threatens jail time, deportation, or loss of a business or driver's license unless the victim pays off the debt immediately via wire transfer or by using a prepaid debit card.

Jennifer Jenkins, a spokeswoman for the IRS, describes a tax-season scam that already has bilked thousands nationwide out of more than $1 million. Officials say it's one od the largest scams to ever target taxpayers.

"It's unusual that a day goes by we don't get a call about this particular phone scam," said Jennifer Jenkins, an IRS spokeswoman based in Columbus.

The IRS began warning about the calls in October. By mid-March, more than 20,000 people had reported getting the dubious calls, many of which had been convincing enough to work.

"The increasing number of people receiving these unsolicited calls from individuals who fraudulently claim to represent the IRS is alarming," J. Russell George, the Treasury inspector general for tax administration, said in a statement.

Tax-season scams are nothing new, but Jenkins said this one "unfortunately has legs."

"People are falling for it," she said. "It's playing off fear."

According to George, the bogus calls share some commonalities:

• The callers use common names and rattle off fake IRS badge numbers.

• They know the last four digits of the victim's Social Security number.

• They make the caller ID information appear as though it's the IRS calling.

• They send bogus emails that appear to be from the IRS to support the scam.

Sometimes the calls are followed up by more bogus phone calls from people claiming to be police officers or Bureau of Motor Vehicle officials to bolster the threats.

The callers are aggressive and authoritative, Jenkins said, and sound as though they're calling from an office space bustling with background noise appropriate for the IRS.

"It's a coordinated effort," said Jenkins, adding that no one has yet been arrested or charged in connection with the fraud.

Fred Colucci, a state coordinator for the AARP Foundation Tax-Aide in southern Ohio, said volunteers are warning the 15,000 taxpayers they expect to help this season about the scam.

"We tell our folks routinely that the IRS will never call you, will never email you, will always write you an official letter," Colucci said. "This doesn't just happen with the IRS. Nobody sends you emails or calls you, at least no reputable organization like a bank or the IRS. They're going to write you a letter.

First-person accounts of the bogus calls are popping up nationwide. Halah Touryalai, a writer for Forbes magazine, described how panic set in when a man called and threatened to suspend her passport and driver's license and seize her assets over $4,900 the caller said she owed the IRS.

She didn't become suspicious until he said she could avoid a legal mess by paying the $4,900 within an hour.

Jenkins assured that no matter what hard-nosed reputation the IRS might have, its agents aren't ever as aggressive as the callers have been described. They won't threaten jail time, she said, nor will they demand immediate payment.

Instead, they'd want to set up an in-person appointment to go over the tax report in question. If payment is necessary, the agency is usually willing to work out payment plans.

"Most people are honest and want to stay on the right side of the law," Jenkins said. "Unfortunately, they're the ones falling for the scam."?

MORE ON THIS STORY

ID thefts causing tax filing woes

The number of legitimate tax returns denied by the IRS because of identity theft is up this year, said Fred Colucci, state coordinator for the AARP Foundation Tax-Aide in southern Ohio.

He estimates that a couple of dozen returns have been rejected locally so far this year. It's a small percentage of the some 15,000 tax reports the volunteer agency submits to the IRS each year, but he worries it's on the rise.

False promises of inflated refunds. Scammers posing as tax preparers lure victims in by promising large federal tax returns. The bogus refunds are often deposited into the tax preparer's account, from which he deducts a fee.

Hiding income offshore. Some people evade U.S. taxes by hiding income in offshore banks, brokerage accounts or nominee entities. Taxpayers with such accounts need to comply with reporting requirements.

Impersonation of charitable organizations. This fraud often occurs in the wake of natural disasters, such as earthquakes or hurricanes. Scammers try to get personal financial information or Social Security numbers to steal victims' identities or financial resources.

WHAT TO DO

If you get a call for someone claiming to be with the IRS and asking for payment, take these steps:

• Hang up and call the IRS at 800-829-1040 if you think you might owe taxes. IRS workers will answer payment questions.

• If you don't owe taxes, report the call to the Treasury Inspector General for Tax Administration at 800-366-4484.

• File a complaint with the Federal Trade Commission at www.FTC.gov. Add "IRS Telephone Scam" in the comments portion of the complaint.

• Do not arrange payment of the supposed debt. The IRS will not ask for immediate payment via wire transfer or prepaid debit cards.

Sources: Treasury Inspector General for Tax Administration and the IRS